The short version
30-second read- A death costs 40% of your personal points. The raid carries on and you can rejoin, though raid-made potions and food you carried are dropped.
- Purple chance caps at 65.7%. That takes 570,000 team points, and points beyond it roll extra uniques, up to six in one raid.
- Carry a pickaxe, fire runes and freeze runes. Guardians and Ice Demon stall teams when someone forgets them, the most annoying learner mistake.
- Save supplies for Olm's final phase. Most deaths happen at the Great Olm, so that reserve matters more than clearing rooms fast.
Overview
Chambers of Xeric (CoX) is the first OSRS raid, released on 5 January 2017, under Mount Quidamortem in the Kebos Lowlands. Teams of 1 to 100 players clear two floors of randomly picked combat, puzzle and resource rooms, then fight the Great Olm on the third. There is no quest requirement, and the quickest ways there are the Lovakengj minecart and fairy ring BLS.
CoX is the most forgiving raid for a weak player. A death costs 40% of your personal points instead of ending the run, most rooms can be carried by a stronger teammate, and there is no invocation system to accidentally over-tune. That is why almost every raider starts here.
The sections below go through access, the room pool, how points translate into unique chances, the Great Olm fight, and the difference between a learner run and an efficient one.
| Detail | Value |
|---|---|
| Type | Procedurally generated three-floor raid |
| Released | 5 January 2017 |
| Location | Under Mount Quidamortem, Kebos Lowlands |
| Hard requirement | No quest. You only need to reach Mount Quidamortem |
| Team size | 1 to 100 players; room enemies scale with party size |
| Final boss | The Great Olm |
| Headline uniques | Twisted bow, elder maul, kodai insignia, dragon claws, ancestral robes |
| Difficulty system | Normal, or Challenge Mode (four floors instead of three) |
Requirements and Access
CoX has no quest requirement, which makes it unusually accessible. The real barrier is travel and the gear needed to contribute meaningfully.
| Requirement | Detail |
|---|---|
| Quest requirement | None. There is no quest gating entry to the raid itself. |
| Mount Quidamortem access | Lovakengj minecart (20 coins a ride, free after The Forsaken Tower), or fairy ring BLS and a short run west and up the north-west path. |
| 43+ Prayer | Protection prayers; 74+ for Rigour, 77+ for Augury. Both make a real difference at Olm. |
| Two usable combat styles | Rooms and Olm's phases demand different styles. One-style accounts are severely limited. |
| A team, or a very strong solo setup | Solo CoX is possible but slow; learning in a team is far faster. |
A Xeric's talisman will not reach the raid on your first trip. Its Xeric's Honour teleport to the summit of Mount Quidamortem only unlocks after you use an ancient tablet on it, and the tablet comes from the raid's reward chest. Until then, the minecart or fairy ring is your fastest route.
Suggested Stats
CoX scales with your team, so you can enter under-levelled and still contribute. These are the levels where you stop being carried.
| Stat | Learner | Comfortable |
|---|---|---|
| Ranged | 80+ | 90+ |
| Magic | 80+ | 90+ |
| Attack / Strength | 80+ | 90+ |
| Hitpoints | 80+ | 90+ |
| Prayer | 43+ | 74+ for Rigour, 77+ for Augury |
| Defence | 70+ | 80+ |
Gear Setups
CoX rewards versatility over specialisation because the room pool is random. Bring a competent option in at least two styles rather than one best-in-slot setup.
| Slot | Budget | Mid | Best in slot |
|---|---|---|---|
| Ranged weapon | Rune crossbow | Toxic blowpipe / Dragon hunter crossbow | Twisted bow / Zaryte crossbow |
| Magic weapon | Trident of the seas | Trident of the swamp | Sanguinesti staff / Tumeken's shadow |
| Melee weapon | Dragon scimitar / Abyssal whip | Abyssal tentacle / Dragon hunter lance | Scythe of vitur |
| Head | Helm of neitiznot | Armadyl helmet / Neitiznot faceguard | Masori mask (f) / Torva full helm |
| Body | Black d'hide body | Karil's leathertop / Bandos chestplate | Masori body (f) / Torva platebody |
| Legs | Black d'hide chaps | Armadyl chainskirt / Bandos tassets | Masori chaps (f) / Torva platelegs |
| Cape | Ava's accumulator | Ava's assembler / Fire cape | Ava's assembler / Infernal cape |
| Amulet | Amulet of fury | Necklace of anguish / Amulet of torture | Necklace of anguish / Amulet of rancour |
| Ring | Explorer's ring | Archers ring (i) / Berserker ring (i) | Lightbearer |
| Boots | Snakeskin boots | Ranger boots / Dragon boots | Pegasian boots / Primordial boots |
A dragon hunter crossbow or lance pays off at the Great Olm, the only draconic monster in the raid.
Bring a salve amulet if your team's route includes the undead rooms; it is a large damage gain for little cost.
Team Roles and Scales
CoX does not have hard roles the way Theatre of Blood does, but teams naturally split responsibilities, and knowing which one you are taking makes runs much smoother.
- 1
Freezer
— handles ice spells for the rooms and Olm phases where freezing controls the fight.
- 2
Main DPS
— brings the strongest damage option and focuses on killing things quickly.
- 3
Skiller
— handles the Thieving room, the herb plots and fishing in each resource room, and the Crabs puzzle.
- 4
Olm hands caller
— during the Great Olm, calls which hand to attack and when phases change.
- 5
Learner
— a legitimate role. Say so, stay alive, and let the team carry the rooms you do not know yet.
Room and Path Overview
Each raid draws rooms from a shared pool across three floors, so no two runs are identical. Knowing the pool means you are never surprised, only occasionally inconvenienced.
| Room | Kind | What it asks of you |
|---|---|---|
| Tekton | Combat boss | Melee-focused fight with an anvil phase; movement and timing matter more than raw DPS. |
| Vasa Nistirio | Combat boss | Crystal mechanics and repositioning; ranged and magic friendly. |
| Vespula | Combat boss | Get Vespula to 20% so she lands, then destroy the abyssal portal. Feed the lux grubs so they never hatch into soldiers that heal her. |
| Muttadiles | Combat boss | Two-stage fight with a tree mechanic that punishes ignoring it. |
| Vanguards | Combat boss | Three enemies whose HP must stay within 40% of each other (33.3% for five or more players), or all three heal to full. |
| Guardians | Combat | Two guardians that only take damage from a pickaxe. A better pickaxe and higher Mining kill them faster. |
| Lizardman Shamans | Combat | 2 to 5 shamans depending on party size. Use a long-range weapon, bring a sanfew serum and stay out of the poison splats. |
| Skeletal Mystics | Combat | 3 to 12 mystics depending on party size. Kill them with ranged; Protect from Magic roughly halves their damage. |
| Ice Demon | Puzzle | Light four braziers with kindling chopped in the corridor, then use fire spells. Most other damage is cut by 67%. |
| Tightrope | Puzzle | Agility-based crossing with ranged enemies; keep prayer up. |
| Crabs | Puzzle | Positioning puzzle solved by aligning the crabs correctly. |
| Thieving | Puzzle | Open chests for cavern grubs and fill the trough. Each grub is worth 115 points, and 60+ Thieving opens more chests. |
| Resource room | Supplies | One per floor: two herb plots (55+ Farming for the raid herbs), plus either fishing spots baited with cave worms (dropped by scavengers) or guanic bats to catch with a butterfly net; both are cooked into raid food. |
| The Great Olm | Final boss | Always the last room. Phase-based fight with two hands and a head. |
The room pool is why versatility beats specialisation. If you cannot cast fire spells, the Ice Demon room becomes a wall, so bring the runes. Ice Demon, Shamans, Mystics and Guardians, the rooms that stall learners most, each get a full write-up in the CoX combat rooms guide.
Challenge Mode and Difficulty
CoX has no invocation system. Instead it offers Challenge Mode, a harder version where every combat and puzzle room appears, enemies get higher stats and hitpoints, and you clear four floors instead of three. Its unique table carries fewer prayer scrolls, so a purple is more likely to be a valuable item.
Because there is no dial to tune, the only difficulty decision you make is normal versus Challenge Mode, and team size. Both are simple, which is another reason CoX is the friendliest raid to learn.
| Option | What changes | Who it is for |
|---|---|---|
| Normal mode | Standard room difficulty and length. | Everyone learning, and most efficient farming. |
| Challenge Mode | Every room appears, four floors, stronger enemies, fewer prayer scrolls on the unique table. | Teams that already clear normal mode comfortably. |
| Solo | You do every room yourself; scaling adjusts enemy stats. | Players with strong gear who want full control. |
| Small team (2–4) | Faster than solo, better personal point share than large teams. | The standard efficient farming size. |
| Large team / mega scale | Far more team points, split across more players. Scaled rooms take longer. | Learners in big clan runs, and groups stacking points for several unique rolls. |
Mega scale CoX is a play pattern, not a game mode. See mega scale CoX explained for how the large-team approach works.
Boss Mechanics That Decide Runs
The Great Olm is the fight that decides most runs, and its mechanics are the ones worth learning first because every raid ends with them.
| Mechanic | What it does | Correct response |
|---|---|---|
| Olm's hands | Two hands must be disabled to progress the head phase. | Assign hands to specific players. Uncoordinated hand damage stalls the fight. |
| Head phase attacks | Olm's head uses attacks requiring correct protection prayers. | Pray according to the attack shown; do not rely on a fixed rhythm. |
| Crystal burst | Crystals appear beneath players and deal damage where they stand. | Move off the crystal tile immediately. |
| Healing pools | Olm can heal in specific phases if the mechanic is ignored. | Handle the mechanic as assigned rather than tunnelling on damage. |
| Final phase | Olm's last phase is the most dangerous part of the raid. | Save supplies for it. Most raid deaths happen here, not in the rooms. |
| Room-specific mechanics | Guardians need a pickaxe, Ice Demon needs fire spells, Vanguards need balanced damage. | Bring the utility items. A missing pickaxe or fire rune stalls the whole team. |
Death and Wipe Mechanics
A death in Chambers of Xeric removes 40% of the personal points you had at that moment, but the raid carries on and you can rejoin it. That is the single biggest reason CoX is the best raid to learn in. A mistake is expensive, not fatal.
Your own gear is safe, but you drop the raid-only items you were carrying, such as the potions and food made inside the raid. Repeated deaths quietly end your raid by leaving you with nothing to contribute, so track your remaining supplies honestly rather than dying twice and hoping.
Most deaths happen at the Great Olm, which is why saving supplies for the final phase matters more than clearing rooms fast.
Points and Reward Mechanics
CoX rewards are point-based, and understanding the two kinds of points is what separates people who farm CoX from people who just run it.
- Total team points set the purple chance. Every 8,676 points is a 1% chance at a unique, capped at 65.7% (570,000 points) for one roll.
- Points above 570,000 roll for another unique, up to six uniques in one raid.
- Your personal points decide who receives a rolled unique. The bigger your share of the team's points, the likelier it lands on you.
- Common loot from the chest scales with personal points up to 131,071. Points past that still count toward uniques.
- Points come from damage dealt, puzzle and skilling rooms, cooking, potions and building storage units.
- A death removes 40% of your personal points, which is the real cost of dying.
- Larger teams generate points faster but split personal share across more players.
| Unique | Weight | Share of purples |
|---|---|---|
| Dexterous prayer scroll | 14/60 | 23.3% |
| Arcane prayer scroll | 14/60 | 23.3% |
| Twisted buckler | 4/60 | 6.7% |
| Dragon hunter crossbow | 4/60 | 6.7% |
| Ancestral hat, robe top, robe bottom | 4/60 each | 6.7% each |
| Dinh's bulwark | 3/60 | 5% |
| Dragon claws | 3/60 | 5% |
| Elder maul | 2/60 | 3.3% |
| Kodai insignia | 2/60 | 3.3% |
| Twisted bow | 2/60 | 3.3% |
The prayer scrolls dropped from a weight of 20 to 14 each on 12 August 2026, so a purple is now 1 in 30 to be a Twisted bow. Challenge Mode uses its own table with the scrolls at 12/56. The Olmlet pet is only rolled when you get a broadcast unique, at 1/53 on that roll. Weights are from the Ancient chest page on the wiki.
Beginner Strategy
Your first raids should be about learning the rooms, not contributing maximum damage. Tell your team you are learning. Competent CoX groups expect it.
- 1
Join a learner-friendly team rather than attempting solo first.
- 2
Bring a pickaxe, fire runes and freeze runes.
Missing utility items is the most annoying learner mistake.
- 3
Say which rooms you do not know before the raid starts.
- 4
In combat rooms, prioritise staying alive over damage.
Points lost to death are worse than points not earned.
- 5
Learn Guardians and Ice Demon early.
They are the two rooms that stall teams when someone forgets a pickaxe or fire runes.
- 6
At Olm, take a single hand assignment and do only that until the fight makes sense.
- 7
Save at least a third of your supplies for Olm's final phase.
- 8
After each raid, ask which room cost the team the most time, and learn that one next.
Advanced Strategy
- Move between rooms without waiting. The fastest teams are already walking while the last enemy dies.
- Learn every room from both a DPS and a freezer position so you can fill whichever slot the team needs.
- Pre-plan Olm hand assignments before the fight rather than calling them mid-phase.
- Use the lightbearer for special-attack-heavy setups; the special regeneration difference compounds across a full raid.
- Pick team size for your goal: small teams for personal point share, mega scales for stacking team points.
- Learn Challenge Mode once normal mode is routine. Every room appears, and its unique table has fewer prayer scrolls.
- Track which rooms your team consistently loses time in and drill those specifically rather than running more raids.
FAQ
Where is Chambers of Xeric, and do I need a quest?
It is under Mount Quidamortem in the Kebos Lowlands, and there is no quest requirement. Take the Lovakengj minecart or fairy ring BLS. A Xeric's talisman only teleports there after you use an ancient tablet from the raid on it.
Is CoX the best raid to learn first?
Yes, for most players. Deaths cost points rather than ending the run, there is no invocation system to over-tune, and a team can carry the rooms you do not know yet.
How do purple chances work?
Every 8,676 team points adds 1% to the unique chance, up to 65.7% at 570,000 points. Points past that roll again, up to six uniques per raid, and your personal points decide how likely each one is to land on you. A death costs 40% of your points, which is why dying hurts.
What is the Thieving room in Chambers of Xeric?
A puzzle room where you open chests for cavern grubs and fill a trough with them. Each grub is worth 115 points, and 60+ Thieving gives a better chance of opening each chest. It is usually the skiller's job while the rest of the team moves on.
What utility items should I always bring?
A pickaxe for Guardians, fire runes for the Ice Demon, and freeze runes if you are taking the freezer role. Forgetting these stalls the whole team.
Should I do solo or team CoX?
Team, while learning. Solo is a good goal later but it is a slow and unforgiving way to learn twelve different rooms plus Olm.
What is mega scale CoX?
A raid packed with far more players than a normal team, up to the 100-player cap, so team points go well past the 570,000 that one unique roll can use. It is a strategy, not a separate game mode. See mega scale CoX explained.
Still stuck on a mechanic? Ask the team on our Discord, it is free.
Bottom Line
Chambers of Xeric is the raid to learn first because it forgives you. Deaths cost points instead of the run, teams can cover rooms you do not know, and there is no difficulty dial to accidentally over-tune.
Bring versatility rather than one strong style, carry the utility items, and save supplies for Olm's final phase. That is where raids are actually lost.
If you want CoX completions before you have learned every room, our CoX raids service is hand-played by our PvM team.
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